aw hek yeah this is awesome man!
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This is a really cool bend, great work.
I ordered one of these boards after watching the LoneryShy videos on YouTube about it, figured I’d tried to make it into Kosmo format. Was thinking I’d just add a pot to bring down the input signal and then use a separate line-level booster module to bring it back up since I’ll have some spare LM chips from the Devil’s Triangle drone I’m planning…
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ah man. so freaking cool🤘🏿
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thx, yes it’s a very fun stuff, also with some voices, and all sources what you want with the external input jack with attenuator pot 
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I through this together this morning, but I’m having some issues with grounding, I think. @Dud - How do you wire up the microphone and output jacks? They aren’t labeled on the board. I’ve just got one going to tip and the other going to ground, but I don’t think that’s right. I’ve got the switches grounded as well. Do you remember how you did yours?
For the microphone, I simply unsolder it and lengthened it with wires.
For the output, look at the speaker for polarity, it seam to be that on the picture (not sure)
or with a multimeter
and yes one for tip and other to gnd
i also add a resistor (surely 8 ohm like the speaker) on the output jack (tip to gnd), and an attenuator pot to control the output volume.
For the switch i 'm not sure what you mean
For the push switch i add wire on the solder point and add a new push switch (so there are still the old switches in place)
and there’s also the Loop switch
if you have others questions
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Oooooh, okay, I think I’ve got you now. Just pinned this out as you had it and seems to work? I have a switch between the bottom left and the top right, and when I flip that it goes into record mode, but all audio stops. When I turn the power on and off again, it starts up in loop mode. So, if I have the +5v on a switch as you have in the picture, then I can toggle the switch to power cycle it and start the loop. Suits me!
Annoyingly, there is a slight gap in between playbacks while it’s looping, which makes it not quite perfect for drones, which I what I was hoping to use it for. Maybe I can bandage over that with reverb and filtering…
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The outputs on the isd chip are based of an internal virtual ground I suspect or some kind of push-pull amp. Grounding the negative terminal of the speaker output will significantly reduce output volume, complete pita for us that want line out. I feed my speaker + into a pt2933 echo chip and leave the negative floating which works ok. I’ve also seen an op amp circuit that sorts it out but I haven’t tried it.
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I’ve been futzing about with these for a while, as they are pretty easy projects to play with. I’m wondering if I could put together a version in KOSMO format, but I’m not entirely sure how I would bring the voltage down from 12v off the rack’s PSU down to the 5v-ish range to power the module. If anybody has any bright ideas I’m open to them!
LM78L05 voltage regulator 
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Thanks! My knowledge of these is very limited so I’ll go research them in more depth. 
Typo corrected above. Here is the datasheet.
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Hi there,
i built the “DIY 4 channel isd1820 lo-fi SAMPLER” from youtube:
See picture (wiring diagram)! It works very well, as an option he added an RC filter schematic as an additional option, I would like to have this RC filter, but unfortunately it does not work.
Question: Should the RC filter circuit work as shown, or does anyone have another idea?
Regards
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That’s a passive RC low pass filter.
The cutoff frequency can vary from 1.6 Hz upwards, in principle to infinity, in practice maybe to 100 Hz or so. The effect definitely should be audible. I’d go with something more like either a 10k pot or a 100 nF cap for a range more like 16 to ~1000 Hz, and I’d use an audio taper pot.
If yours didn’t work then I’d say either you made some mistake in construction, or perhaps whatever you’re feeding it into sabotaged it, maybe by having too low impedance or by itself imposing a filter with a higher cutoff.
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@peppy
Thanks for designing this! I will combine yours and @Dud 's for pitch cv and ext.gate. I will come back with the results! Let’s see how how small I can make for my 3U synth.
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…gladly ! Please note, the LED must be soldered in the other way round, on the stripboard it is the wrong way around (see also schematic):
I added Record In and Tigger IN for my eurorack system, works great
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Thanks again, I have now used A100k pot with 0.33uf and it works! I think 1uf was too much. I’m looking for a simple circuit on the internet as I can activate the passive filter with a “TL072”.